tbuckley/cabot-search huggingface dataset:
PB2483: INVESTIGATING THE EFFECT OF CYTOCHROME C MUTATION ON MEGAKARYOCYTE DIFFERENTIATION
Authors: Zahra Shafaei Pishabad
Journal: HemaSphere (2023)

Topic: 23. Hematopoiesis, stem cells and microenvironment Background: Mutations in genes which play a role in the processes of megakaryopoiesis and platelet production cause thrombocytopenia. Five pathogenic variants in the gene encoding cytochrome c (CYCS) associated with mild autosomal dominant thrombocytopenia have been reported. The role of cytochrome c in megakaryopoiesis and platelet formation is unknown, and it is unclear how mutations in cytochrome c cause thrombocytopenia. Aims: Investigating the effect of Y49H mutation in megakaryocyte maturation of K562 cells. Methods: We are using the human leukemic K562 cell line as a model system to study the impact of CYCS mutations on megakaryocyte differentiation and mitochondrial function. One of the CYCS pathogenic variants (c.145T>C; p.Tyr49His) was introduced into K562 cells using the CRISPR-Cas9 base-editing method. K562 cells have three copies of CYCS-containing chromosome 7 and we isolated CYCSWT/WT/WT, CYCSWT/WT/Y49H, CYCSWT/Y49H/Y49H, CYCSY49H/Y49H/Y49H clonal lines, confirmed by sequencing and mass spectrometry. K562 cells undergo megakaryocyte differentiation in response to PMA. We monitored the expression of megakaryocyte markers CD61 and CD41a by flow cytometry in response to PMA in all clonal lines. Due to presence of the mutation in CYCS we assessed mitochondrial function using the Seahorse XFe96 Analyzer, and also caspase depended apoptosis in all Y49H clonal lines. Results: The K562-CYCSY49H/Y49H/Y49H line, which has three mutant alleles, showed faster maturation toward megakaryocytes compared to all other clonal lines and the parental K562 cells. Our results also show that the Y49H mutation does not impact mitochondrial function. Summary/Conclusion: To date our results suggest that the pathogenic c.145T>C; p.Tyr49His CYCS variant enhances megakaryocyte maturation. Keywords: Megakaryopoiesis
PB2176: MRNA OF MPL AND JAK2 GENES IN PLATELETS IS ASSOCIATED WITH THEIR ASPIRIN RESISTANCE IN MPN PATIENTS
Authors: Marina Stolyar, Igor Olkhovskiy, Aleksey Gorbenko
Journal: HemaSphere (2023)

Topic: 15. Myeloproliferative neoplasms - Biology & Translational Research Background: Various qualitative and quantitative platelet abnormalities in myeloproliferative neoplasms (MPN) have been described. For this reason, patients with MPNs are at risk of both thrombotic and bleeding complications (Thomas S. et al., Arterioscler Thromb Vasc Biol, 2021). Decreased sensitivity to aspirin in patients with MPN is known, and we have also previously observed this in our patients who received it for the thrombosis prevention (Olkhovskiy I.A., 2014). Previously, we investigated the significance of mRNA JAK2 (Olkhovskiy I. et al., EHA, 2020, PB2135) and mRNA MPL genes (Stolyar M.A. et al., Int J Lab Hematol, 2019) in platelets from MPN patients, but did not compare them with aspirin resistance. Aims: Study of the level mRNA MPL and JAK2 genes in platelets for influence on platelet aggregation in the presence of aspirin. Methods: Blood samples from 27 MPN patients (polycythemia vera, n=19; essential thrombocythemia, n=8) were used. An impedance aggregometry method was performed using CHRONO-LOG 700 and ADP (5 μM) as an inducer and with or without aspirin (ASA; 0.1 mM). Quantitative real-time PCR analysis for the detection of MPL and JAK2 mRNA in platelets was performed using the CFX96 system (Bio-Rad, Hercules, CA, USA) with TaqMan probes and primers in the Gene Formula kit. Results: Studied population was divided in two groups according to the response to ASA: ASA resistant (n=21) and ASA sensitive (n=8). In our study, it was shown that in ASA resistant group an increase in mRNA MPL and JAK2 expression was observed (Figure). In our study, it was shown that in the ASA-resistant group, an increase in the total expression of both MPL mRNA and JAK2 mRNA was observed, regardless of the mutation status.Summary/Conclusion: Thus, it can be assumed that the increased expression of these genes is involved in the signaling pathways of platelet aggregation activity and prevents of the ASA effect. Keywords: Aspirin, Platelet aggregation, Myeloproliferative disorder
PB2234: EFFECT OF HYDROXYUREA ON INFLAMMATORY MARKERS IN PATIENTS WITH BCR-ABL NEGATIVE MYELOPROLIFERATIVE DISEASES
Authors: Oguz Altunok, Istemi Serin, Osman Yokus
Journal: HemaSphere (2023)

Topic: 16. Myeloproliferative neoplasms - Clinical Background: Myeloproliferative neoplasms (MPN) describe a group of diseases characterized by increased proliferation of the myeloid series in the bone marrow. MPNs are classified into four different subgroups: 1) Chronic Myeloid Leukemia (CML), 2) Philedelphia chromosome-negative classical MPNs such as Polycythemia Vera (PV), Essential Thrombocythemia (ET), Primary Myelofibrosis (PMF), 3) Non-classical Philadelphia chromosome-negative MPNs (Chronic Neutrophilic Leukemia, CNL; Chronic Eosinophilic Leukemia, CEL) and 4) Unclassifiable-MPN (MPN-u). Aims: In our study, we aimed to reveal the possible effect of hydroxyurea on inflammation as the cytoreductive treatment of BCR-ABL negative MPNs. Methods: In this study, BCR-ABL negative MPNs were grouped as PV, ET, PMF and others. Subtype of diagnosis, age, gender, genetic mutations at the time of diagnosis, treatment and follow-up preferences, laboratory results (leukocyte, neutrophil, thrombocyte, C - reactive protein (CRP) and lactate dehydrogenase (LDH)) at 0.-3.-6. and 12.months were recorded. Alterations in inflammatory indicators such as leukocytes, neutrophils, CRP, LDH, neutrophil- lymphocyte ratio (NLR) and systemic immune inflammatory index (SIII) were examined in patients who treated with hydroxyurea. Results: A total of 298 patients; 121 females (%40.6) and 177 males (%59.4) were included in our study. While 70 patients were in MPN-u group (%23.49), 97 patients in PV (%32.55), 105 patients in ET (%35.23) and 26 patients were in PMF group (%8.72). Fifty-three percent of total and 92 percent of patients with cytoreductive therapy were receiving hydroxyurea. There was a considerable decrease neutrophil and leukocyte values between 0.-3.,0.-6. and 0.-12. months in patients receiving hydroxyurea (p<0.001). Also in the same group, significant decrease in NLR was detected between 0.-3. and 0.-6. months (p=0.001 and p=0.01). In terms of the systemic immune inflammatory index, a significant decrease was found between 0.-3., 0.-6. and 0.-12. months (p<0.001). Summary/Conclusion: In this study, we found a statistically significant decrease in neutrophil, leukocyte, NLR and SIII values in the group receiving hydroxyurea. The decrease in SIII which includes neutrophil and platelet values was more remarkable. We think that the study should be evaluated together with cytokines in a larger patient group in order to mention the effect of hydroxyurea on inflammation more clearly.Keywords: Myeloproliferative disorder, Hydroxyurea, Inflammation
PB2274: REAL-WORLD OUTCOME OF FOLLICULAR LYMPHOMA IN TAIWAN: A MULTICENTER REGISTRY STUDY
Authors: Bor-Sheng Ko, Ming-Chung Wang, Kuan-Ming Lai, Tsai-Yun Chen, Chieh-Lin Teng, Tran-Der Tan
Journal: HemaSphere (2023)

Topic: 18. Indolent and mantle-cell non-Hodgkin lymphoma - Clinical Background: Follicular lymphoma (FL) is a type of indolent non-Hodgkin lymphoma with increasing incidences in Taiwan. The treatment pattern and outcome in Taiwan were not well characterized yet Aims: This study was aimed to illustrate the characters, treatment pattern and outcome in Taiwan FL patients. Methods: This retrospective study enrolled patients who were pathologically diagnosed as FL from January 2008 to December 2018 in 6 medical centers in Taiwan. Patients with pathological grade I to IIIb were all enrolled. Their clinical characters, treatment and outcome were all subjected to analysis. Results: Totally 312 patients were enrolled, with a median follow-up of 59.3 months. Their median age was 58.1 y/o with slight female predominance (Table 1). Good performance (ECOG 0-1) was noted in 68.5% (196/288) of patients. Bone marrow involvement (50.9%, 146/287) and advanced Ann Arbor stage (III/IV, 58.4%, 190/295) were common. Elevated LDH was noted in 20.5% (59/288) of patients. After diagnosis, only 14.5% (45/311) patients did not receive treatment, and the rest seemed to receive treatment soon (average 0.80±6.93 months). Chemo-immunotherapy was most frequently used (78.3%, 246/311). Their 5-year rates of overall survival (OS) and progression-free survival (PFS) were 82.3±2.5% and 66.9±3.3%, respectively. FL-IPI could predict PFS (5-year PFS rate, low (0-1) vs. intermediate (2-3) vs. high (4-5): 84.7±5.0% vs. 68.3±4.7% vs. 38.4±9.7%, p<0.001) and OS (5-year OS rate, low vs. intermediate vs. high: 96.8±2.2% vs. 85.8±3.4% vs. 49.5±9.8%, p<0.001). After 1st relapse, progression of disease with 24 months (POD24), as noted in other studies, could predict overall survival (5-year OS rate: 54.2±10.7% vs. 86.6±9.0%, p=0.04) Summary/Conclusion: Although with similar presenting characters as in Western countries, Taiwan FL patients received treatment early after diagnosis. Their OS and PFS were good, and FL-IPI was of predictive significance. After progression, POD24 could still predict outcome.Keywords: Follicular lymphoma, Lymphoma, Non-Hodgkin’s lymphoma
PB2367: CLINICAL CHARACTERISTICS AND PROGNOSIS OF PATIENTS WITH NODAL PERIPHERAL T-CELL LYMPHOMA
Authors: Noura Ben Yahia, Maha Charfi, Faten Kallel, Imen Ben Amor, Yousra Fakhfakh Derbel, Imen Frikha, Khelifa Latifa, Moez Medhaffar, Olfa Kassar, Sondes Hadiji Mseddi, Moez Elloumi
Journal: HemaSphere (2023)

Topic: 19. Aggressive Non-Hodgkin lymphoma - Clinical Background: Peripheral T-cell lymphoma (PTCL) is a highly heterogeneous invasive non-Hodgkin’s lymphoma (NHL) originated from mature T cells. PTCL represents 10-15% of NHL patients. The clinical manifestations are variable from one entity to another within the PTCL. Aims: The aim of this study is to describe clinical characteristics and prognostic factors of a cohort of patients with nodal PTCL in south Tunisia. Methods: Our study is retrospective, it involved patients with nodal PTCL treated in the hematology department of Sfax between January 2000 and June 2021.We studied Clinical and laboratory data. The diagnosis was confirmed by histological examination according to the 2016 World Health Organization classification of hematologic malignancies. Staging was performed according to Ann Arbor system after extension assessment which includes at least a CT scan and bone marrow biopsy. Results: Thirty-eight patients diagnosed with PTCL were registered. The most common histological subtype was PTCL not otherwise specified (PTCL NOS) (n=14, 37%) followed by anaplastic ALK negative T-cell lymphoma (ALCL ALK-) (n=12, 31%), angioimmunoblastic T-cell lymphoma (AITL) (n=9, 24%) and then (ALCL ALK+) (n=3, 8%). The median age was 51 years (17- 87) among whom 12 patients (32%) were >60 years old. The sex ratio was 2.4, the male predominance was found in all histological subtypes. A history of autoimmune disease was noted in patients with AITL such as vitiligo and psoriasis in one case each. A history of skin rush was observed in one case. B symptoms were present in 76% of cases. A performance status >= 2 was present in 40% of patients. The most common discovery circumstance was the presence of peripheral adenopathy (40% of cases) with cervical adenopathy being the most common localization. Splenomegaly was present in 29% of cases mostly seen in AITL (55%) and PTCL NOS (36%). Nine patients had hepatomegaly (24%). Pleural and pericardial infiltration were noted in one patient with AITL. Testicular and breast involvement were noted in one case of PTCL NOS each. Increased LDH level was noted in 60.5% of cases. An extended stage (III-IV) was found in 82% of cases. The most frequent extra-nodal localization was bone marrow infiltration (48%). Summary/Conclusion: The clinical and prognostic data in our patients are generally similar to previous reports in the literature. However, 48 % patients in this study had bone marrow infiltration, slightly higher than that in previous studies by 20%–30%. PTCL has a poor prognosis and several studies have shown that histological subtypes, Ann Arbor stage and bone marrow involvement are related with the prognosis of PTCL patients. Keywords: T cell lymphoma, Angioimmunoblastic T-cell lymphoma, Peripheral T-cell lymphoma, Chemotherapy
PB2034: TARGETED SEQUENCING LANDSCAPE OF A CHINESE PURE RED CELL ANEMIA COHORT
Authors: Yue LI, Xiaoqing Liu, Xinyu Zhang, Yuemin Gong, Guangsheng He, Jianyong LI
Journal: HemaSphere (2023)

Topic: 11. Bone marrow failure syndromes incl. PNH - Biology & Translational Research Background: Primary pure red cell aplasia(PRCA) and secondary PRCA associated with large granular lymphocyte leukemia are generally considered to be immune-mediated. The PRCA 2004/2006 study showed that poor responses to immunosuppression and anemia relapse were associated with death. PRCA may represent the prodrome to MDS. However, the underlying mechanism was still unclear. Aims: We investigated gene mutations in myeloid neoplasm-associated genes in PRCA, in order to clarify the gene mutation landscape of PRCA, especially the difference between primary PRCA and T-LGLL associated PRCA. Methods: Clinical characteristics were collected. Extracted genomic DNA samples from peripheral blood were subjected to targeted sequencing for 63 myeloid malignancy-associated genes using a MiSeq system and a TruSight Myeloid Sequencing Panel kit according to Illumina. Heatmaps were generated via Graphpad 9.5. Results: A total of 70 PRCA patients were enrolled in our study, 20 were T-LGLL associated PRCA, 50 were primary PRCA. 37 was males and 43 was females. Median age was 60(22-89) years old. We identified 19 mutations affecting amino acid sequences in of 70 PRCA patients. Overall genomic alterations was shown in Figure 1. Most frequent mutations included TET2(40/70, 57.14%), ASXL1(23/70, 32.86%), GATA2(13/70, 18.57%), MLL(7/70, 10.00%), SETBP1(5/70, 7.14%), RUNX1(4/70, 5.71%), SH2B3(3/70, 4.29%), DNMT3A(3/70, 4.29%). Subgroup analysis of gene mutation frequencies were shown in Figure 2, there was significant difference between T-LGLL associated PRCA and primary PRCA(p<0.05). In primary PRCA group, most frequent mutations included TET2(31/50, 62%), ASXL1(17/50, 34%), GATA2(10/50, 20%), MLL(6/50, 12%), and SETBP1(5/50, 10%). In T-LGLL associated PRCA group, most frequent mutations included TET2(9/20, 45%), ASXL1(6/20, 30%), GATA2(3/20, 15%), DNMT3A(2/20, 10%), and STAT3(2/20, 10%). Summary/Conclusion: We found that rare variants or mutations in myeloid neoplasm-associated genes were detected in PRCA. In our cohort, TET2, ASXL1, GATA2 were frequent in both primary and T-LGLL associated PRCA.Keywords: Somatic mutation, Pure red cell aplasia, T cell leukemia
PB2374: DIFFERENCES IN MUTATIONAL SIGNATURE OF DIFFUSE LARGE B-CELL LYMPHOMAS ACCORDING TO THE PRIMARY ORGAN
Authors: Hyun Hee Koh, Junhun Cho
Journal: HemaSphere (2023)

Topic: 20. Lymphoma Biology & Translational Research Background: Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous entity. Recently, the updated World Health Organization classification and The International Consensus Classification have suggested a more subdivided categorization of DLBCL. Moreover, comprehensive molecular subtyping of DLBCL through genetic profiling has broadened our understanding of DLBCL biology. However, a number of DLBCL cases are still diagnosed as not otherwise specified (NOS), which may also be a set of members of a particular subtype that has not yet been classified. Many of the established subtypes of DLBCL are named according to their primary organs, and there were different therapeutic strategies according to specific sites of DLBCL, suggesting that there may be differences in the tumor biology depending on the primary organ. Aims: In this study, we investigated whether DLBCL NOS shows differences in mutational patterns depending on the primary organ. Methods: Panel-based next-generation sequencing was performed on 345 DLBCLs from various primary organs, and patterns of mutations according to primary organs were analyzed. In addition, discriminant analysis was performed to classify the tumors of each original organ and to predict the belonging group according to the molecular characteristics. Results: DLBCL showed a characteristic mutational signature in several primary organs, and especially the mutational pattern of DLBCL in the breast and ileocecal area was particularly different from that of others (Figure). In breast DLBCL, MYD88 L265P (57.1%), CD79B mutation (42.9%), and CDKN2A/B loss (71.4%) were found at high frequencies, which were like the mutation patterns of DLBCL of immune-privileged sites. DLBCL in the ileocecal area characteristically showed the most frequent TP53 mutation (52.6%) and 18q21 gain (42.1%), which was also different from the mutational pattern observed in the stomach or other intestines. In discriminant analysis, DLBCL of the breast and ileocecal area tended to form separate genetic constellations from others. Summary/Conclusion: In conclusion, DLBCL NOS has a characteristic mutational profile depending on the primary organ, and particularly the mutational signature of DLBCL in the breast and ileocecal area was heterogeneous compared with that of other DLBCL NOS.Keywords: Molecular, Diffuse large B cell lymphoma, Gene mutation
PB2280: MULTISYSTEM ERDHEIM CHESTER NEOPLASM WITH BRAFV660E MUTATION, PROMINENT EMPERIPOLESIS, HEMOPHAGOCYTOSIS AND FULMINANT COURSE
Authors: Dina Soliman, Firyal Ibrahim, Hasan Rizvi, Zsolt Lengyel, Awni Alshurafa, Mahir Petkar
Journal: HemaSphere (2023)

Topic: 18. Indolent and mantle-cell non-Hodgkin lymphoma - Clinical Background: Erdheim-Chester disease (ECD) is a rare clonal proliferation of non-Langerhans cell histiocytes, commonly having a foamy (lipid-laden) cytoplasm & associated with MAPK pathway mutations, frequently BRAF V600E. Aims: This report highlights challenges in diagnosis of rare disease & the role of clinicopathological correlation & molecular diagnosti Methods: This is a report of rare case of ECD with extremely challenging diagnosis, in spite of the extensive work-up including multiple tissue biopsies from different sites. The diagnosis was significantly delayed for > 10 months & unfortunately the patient succumbed due to delayed management & severe MRSA skin infection. This is a 60-year-old male patient, presented with diffuse abdominal pain, unintended weight loss and progressive erythematous skin macules & ecchymotic patches over the shoulders, lower abdomen & the scalp. Results: CBC showed severe anemia with elevated bilirubin & renal function tests. PET CT scan showed sclerotic foci in pelvic & long bones with hypermetabolic bone marrow (BM) & infiltration of peri-nephric fat. Multiple skin, retroperitoneal, duodenal & BM biopsies revealed fibrohistiocytic infiltrate suggestive of an inflammatory process. A repeat BM aspirate showed infiltration by abnormal histiocytes, composed of multinucleated giant forms (with dispersed nuclear chromatin and inconspicuous nucleoli), forms with abundant bluish-black cytoplasm & dense hemosiderin deposition, &/or prominent emperipolesis & small forms exhibiting active hemophagocytosis. The BM biopsy revealed fibroinflammatory foci with areas of collagenization & dense infiltration by abnormal histiocytes; mostly large cells with abundant cytoplasm, inconspicuous nucleoli & some multinucleated forms. The abnormal histiocytes were positive for CD68, CD163, factor XIIIa, PU.1, S-100 (partial), cyclin D1 and negative for Langerin, CD1a & ALK. Molecular analysis revealed BRAF600E concluding ECD diagnosis. Summary/Conclusion: Our case had non-specific findings including lack of foamy macrophages, the presence of emperipolesis (Rosi-Dorfman like cells), hemophagocytosis & hemosiderin deposition. When interpreted with the clinical findings, the detection of BRAFV660E mutation had the decisive role in making the diagnosis. Also, the latter clinical course was more in keeping with macrophage activation syndrome than typical ECD. The unfortunate outcome could be delayed with targeted therapy against the actionable mutationKeywords: Histiocytosis
PB2178: EVALUATION OF JAK2 EXON 12 MUTATIONS IN PATIENTS WITH JAK2 (V617F)-NEGATIVE POLYCYTHEMIA VERA
Authors: Sahar Khosravi, Bahram Chahardouli, Pouyan Ebrahimi, Fatemeh Naghdi Babaei, Kamran Alimoghaddam, Shahrbano Rostami
Journal: HemaSphere (2023)

Topic: 15. Myeloproliferative neoplasms - Biology & Translational Research Background: Polycythemia vera (PV) disease is an acquired and clonal stem cell disorder characterized by abnormal erythropoiesis. Identifying a unique mutation of increased activity in the Janus kinase 2 (JAK2) gene in patients with chronic myeloproliferative disorders has provided a beneficial diagnostic method. Aims: The present study evaluated exon 12 mutations in the JAK2 gene in patients with PV who had no V617F mutation. Methods: This cross-sectional study was conducted on adult patients with PV who were referred to the blood department of Shariati Hospital (Tehran, Iran) between 2013 and 2016. All samples were sent for flow cytometry to check cells for leukemia and cell line. Further, chromosomal karyotype was checked by the metaphase culture method on all samples. In this study, cDNA was isolated from the samples of PV patients without the V617F mutation. Sequencing was performed using the BigDye Terminator Sequencing Kit (Applied Biosystems), version 1.1. The identified sequence was then confirmed by Sanger sequencing. Finally, the presence of the mutation in the determined sequence was examined by DNASIS software. Ultimately, the data were statistically analyzed using SPSS software, version 22. Results: In general, 150 patients with an average age of 46.30±19.50 years were included in this study. In 12 patients (eight percent), mutations were detected in the exon 12 of the JAK2 gene, including two novel genetic mutations (NG_009904.1:g.89793T>G and NG_009904.1 (JAK2_i001)) that had not been reported previously (Figure1). A significant decrease was observed in the platelet count, while a significant increase was found in the hemoglobin level in patients with mutations compared to patients without mutations (P<0.001, P=0.023). Among 23 patients, the average percentage of the bone blast was 1.78±0.95, and out of 25 patients, three cases had mutations in exon 12, and all of them had increased erythropoiesis.Figure 1. Electropherogram of a patient with a newly identified mutation in the JAK2 gene exon 12. The top and bottom pictures show the sample without and with mutations, respectively. The result of sequencing in this patient was the substitution of G nucleotide acid instead of T nucleotide at position 89793, resulting in the substitution of amino acid lysine instead of asparagine at position 542 (Asn542Lys). Summary/Conclusion: Overall, a relationship was found between hemoglobin and platelet levels with mutations in exon 12. In terms of polymorphism, heterozygote was the most common type, and the JAK2 gene mutation in exon 12 was observed in all patients with erythrocytosis. These findings can help better diagnose and find better treatment methods for PV patients in future studies. Keywords: Gene mutation, Mutation, Kinase domain mutant, Polycythemia vera